Improvement in steam and air engines



F. .I. CROUCH.

Steamand Air-Engines.

No.145,281. Patented Dec.9,1873.

'II'I'.

mitmsws. lawman UNITED STATES PATENT OFFIcE.

FRANK J. CROUCH, OF SAN JOSE, CALIFORNIA.

IMPROVEMENT IN STEAM AND AlR ENGINES.

Specification forming part of Letters Patent No- 145,2S1, dated December9, 1673; application filed September 27, 1873.

To all whom it may concern:

Be it known that I, FRANK J. CROUCH, of San Jose',.Santa Clara county,State of California, have invented an Improved Steam and Air Engine; and1 do hereby declare the following description and accompanying drawingsare sufficient to enable any person skilled. in the art or science towhich it most nearly appertains to make and use my said invention orimprovement without further invention or experiment.

My invention consists in superheating ordinary steam at the instant ofputting it under the piston of a steam-engine, so that the full value,of the power developed by superheating it will be obtained in drivingthe piston. To do this, I construct an engine of a peculiar style, whichis at once compact and cheap, and which can be run with very littleexpen e for fuel.

In'orfir to explain my invention so that others will understand itsconstruction and operation, reference is had to the accompanyingdrawings forming a part of this specification, in which--- 7 Figure 1 isa perspective view of my engine. Fig. 2 is a section, showing thecylinders in position over the fire-place. Fig. 3 is a longitudinalsection, in elevation, showing the relative position of the parts.

A is a furnace, which may be constructed of iron or masonry, and isprovided with a fire-place, M. B is an upright boiler, which is mountedupon one end of the furnace A, so that the heat and products ofcombustion from the furnace will pass up through the boiler and stackand heat the water in the boiler in the manner of an ordinary uprightengine and boiler. Upon the opposite end of the furnace, and directlyover the fire-place, I set two upright open-top cylinders, C C, so thattheir lower ends extend down into the fire-place through the top of thefurnace. The pistons D D each consist of a tube of the de sired length,having a partition or diaphragm passing across its middle, thus forminga double cup-shaped piston, the tube serving as a guide to the movingpiston. The pitman F of each piston is secured to the center of thediaphragm at its lower end, while its upper end is secured to a crank onthe crank or driving shaft g. The pistons move up and down in theopen-topped cylinders, being connected by their pitmen to double crankson the crankshaft, so that the upward movement forces the other downalternately.

If desired, the cylinders C C can each be constructed with an inner'tube, which is smaller than the cylinder, and inside of whichthe pistonmoves. In this case, the space between the upper end of the cylinder andtube will be closed, and the tube will not extend quite to the bottom ofthe cylinder, thus providing a space or jacket between the two whichcommunicates below the tube with the space below the piston. Suitablepacking is secured around the pistons in order to render them steamtight in the cylinders. A tube, 1), which is provided with a propervalve, connects either with the space below the piston or with thejacket between the cylinder and its inner tube, through which a quantityof air will be drawn by the pumping action of the piston after theexhaust-valve closes and before the steam-port is opened for theupstroke of the piston.

These air-valves can be used or not, as desired, my improvement inworking steam not depending. upon them, further than to use them asaccessories.

It is the steam-chest, into which the steam is conveyed from the boilerby the pipe S, and T is the exhaustpipe which conveys the ex haust-steamafter each stroke of the piston to the smoke-stack. The steam-valve isoperated by crank, U, connecting-link V, and eccentric W from the maindriving-shaft g.

The fire which heats the water in the boiler also heats that portion ofthe cylinders C O which extends down into the fire-place, and when thusheated, the steam which is admitted below the pistons is suddenlysuperheated by coming in contact with the heated chamber, and its poweris greatly multiplied at the very instant and in the exact situation inwhich it will work effectively.

Superheated steam has heretofore been used in steam-cylinders, but ithas always been superheated in an intermediate heater between the boilerand engine, and introduced into the cylinder in a highly-heatedcondition. While the cylinder was at a much lower temperature,

and while much better results were obtained in this way than in usingsteam at ordinary temperatures, the conditions were such that y thecylinder and piston were soon destroyed by the action of the superheatedsteam; but by my plan the cylinders themselves are kept at the highesttemperature and made to serve as superheaters, as well as cylinders,giving the additional advantage of utilizing the explosion or suddenexpansion caused by superheating at the instant the expansion occurs. Inthe present case I have shown an ordinary slide-valve for working thesteam, but

7 it is manifest that any of the known methods of admitting steam andcutting off at diii'erent parts of the stroke may be employed, as may befound most suitable for the style of engine to be used. By actual testswith my engine a resulting advantage of three to one is obtained byusing steam superheated on cylinder-heaters, as above described, overthe use of steam at ordinary temperatures.

I am aware that water has been injected into the cylinder and thereconverted into steam under the piston. I therefore do not 3. Thecylinders C 0, either with or without the air-valves p, in combinationwith their double cup-shaped pistons D D, pitmen F, and crank-shaft g,substantially as and for the purpose above described.

In witness whereof I hereunto set my hand and seal.

FRANK J. CROUCH. Witnesses:

W. W. S'row, U. M. RICHARDSON.

